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Graham Thompson

Publications and source records attributed to Graham Thompson.

3 recordsLinked to original sources
PubMed2005

Application of FTA technology for sampling, recovery and molecular characterization of viral pathogens and virus-derived transgenes from plant tissues.

BACKGROUND: Plant viral diseases present major constraints to crop production. Effective sampling of the viruses infecting plants is required to facilitate their molecular study and is essential for the development of crop protection and improvement programs. Retaining integrity of viral pathogens within sampled plant tissues is often a limiting factor in this process, most especially when sample sizes are large and when operating in developing counties and regions remote from laboratory facilities. FTA is a paper-based system designed to fix and store nucleic acids directly from fresh tissues pressed into the treated paper. We report here the use of FTA as an effective technology for sampling and retrieval of DNA and RNA viruses from plant tissues and their subsequent molecular analysis. RESULTS: DNA and RNA viruses were successfully recovered from leaf tissues of maize, cassava, tomato and tobacco pressed into FTA Classic Cards. Viral nucleic acids eluted from FTA cards were found to be suitable for diagnostic molecular analysis by PCR-based techniques and restriction analysis, and for cloning and nucleotide sequencing in a manner equivalent to that offered by tradition isolation methods. Efficacy of the technology was demonstrated both from sampled greenhouse-grown plants and from leaf presses taken from crop plants growing in farmer's fields in East Africa. In addition, FTA technology was shown to be suitable for recovery of viral-derived transgene sequences integrated into the plant genome. CONCLUSION: Results demonstrate that FTA is a practical, economical and sensitive method for sampling, storage and retrieval of viral pathogens and plant genomic sequences, when working under controlled conditions and in the field. Application of this technology has the potential to significantly increase ability to bring modern analytical techniques to bear on the viral pathogens infecting crop plants.

Africa↗
PubMed2004

Practice variation among pediatric emergency departments in the treatment of bronchiolitis.

OBJECTIVES: Bronchiolitis is the most common disease of the lower respiratory tract in the first year of life. Treatment is controversial, with studies giving conflicting views on the benefits of bronchodilators and steroids. The objectives of this study were 1) to characterize the management of bronchiolitis in pediatric emergency departments (PEDs) in Canada, 2) to determine patient outcomes following emergency department (ED) visits, and 3) to provide descriptive data regarding bronchiolitis symptoms and family/personal medical history of these patients. METHODS: A prospective consecutive cohort of children with bronchiolitis presenting to seven Canadian PEDs was enrolled during a seven-to-21-day period. Standardized interviews with parents provided data regarding symptoms, previous treatment, and past history. Charts were reviewed for treatment, investigations, and disposition. Telephone follow-up at two to three weeks collected information regarding duration of illness and return visits. RESULTS: Two hundred thirty-seven (91%) of 260 eligible patients were enrolled. One hundred eighty-nine patients (80%) had both an interview and chart review, and 48 (20%) had only chart reviews; follow-up was completed for 163 (69%) patients. One hundred fifteen (63%) had seen their primary care provider during their illness prior to the ED visit. Seventy-three percent of patients (range per site 59-100%) were treated in the ED with bronchodilators (usually salbutamol or epinephrine) and 5% (range per site 0-14%) with oral steroids. Twenty-four percent (58/237) were prescribed bronchodilators on discharge, 3% (7/237) inhaled steroids, and 2% (5/237) oral steroids. Chi-square tests indicated significant practice variation by site in ED bronchodilator use (p < 0.001) and bronchodilator use at discharge (p = 0.0003). Admission rate was 31% (range by site 22-43%), 17% of patients had more than one ED visit, and 1% were admitted more than once. Admission rates were increased in younger children, children with comorbidities, and children with lower oxygen saturation. Viral studies were obtained in 53%, with 76% of these positive for respiratory syncytial virus (RSV). Median duration of cough was 12 days, poor sleeping and irritability eight days, and wheeze and poor feeding seven days. CONCLUSIONS: This study prospectively describes the treatment of bronchiolitis in the pediatric ED. The findings are consistent with the literature regarding the reported use of bronchodilators; however, use of steroids was found to be much lower than reported in other studies. Bronchodilator use in the ED and at discharge varied significantly by site. The results capture variation in treatment practices in Canadian PEDs, which may be the result of discordant randomized controlled trial evidence. Further research is needed to establish best practices.

Bronchiolitis↗